Author: Shamim Rezaie
MDL-71410 mod_quiz: Cache user and group overrides
http://git.moodle.org/gw?p=moodle.git;a=commit;h=e8caa2d2a22b1f58fed37e793d8e9ecf096769a1
http://github.com/moodle/moodle/commit/e8caa2d2a22b1f58fed37e793d8e9ecf096769a1
+ 3.11 en [cachedef_overrides,mod_quiz]